Add initial stack/heap reporting for mdash

tutorials/stm32/nucleo-h723zg/minimal/hal.c

@@ -43,15 +43,15 @@ __attribute__((weak)) int _fstat(int fd, struct stat *st) {
 }
 
 extern unsigned char _end[];  // End of data section, start of heap. See link.ld
+extern unsigned char _estack[];  // Initial stack pointer. See link.ld
 static unsigned char *s_current_heap_end = _end;
 
-size_t hal_ram_used(void) {
-  return (size_t) (s_current_heap_end - _end);
+size_t hal_get_heap(void) {
+  return (size_t) ((uintptr_t) s_current_heap_end - (uintptr_t) _end);
 }
 
-size_t hal_ram_free(void) {
-  unsigned char endofstack;
-  return (size_t) (&endofstack - s_current_heap_end);
+size_t hal_get_stack(void) {
+  return (size_t) ((uintptr_t) _estack - (uintptr_t) __get_MSP());
 }
 
 void *_sbrk(int incr) {

tutorials/stm32/nucleo-h723zg/minimal/hal.h

@@ -15,8 +15,8 @@
 
 extern bool hal_timer_expired(volatile uint64_t *t, uint64_t prd, uint64_t now);
 extern uint64_t hal_get_tick(void);
-extern size_t hal_ram_free(void);
-extern size_t hal_ram_used(void);
+extern size_t hal_get_heap(void);   // Heap bytes reserved through _sbrk()
+extern size_t hal_get_stack(void);  // Stack bytes currently used (MSP)
 extern uint32_t SystemCoreClock;
 
 #define BIT(x) (1UL << (x))

tutorials/stm32/nucleo-h723zg/minimal/main.c

@@ -78,9 +78,9 @@ static void http_ev_handler(struct mg_connection *c, int ev, void *ev_data) {
       mg_http_reply(c, 200, "",
                     "Hi from Mongoose!\n"
                     "tick:     %llu\n"
-                    "ram used: %zu\n"
-                    "ram free: %zu\n",
-                    hal_get_tick(), hal_ram_used(), hal_ram_free());
+                    "heap used:  %zu\n"
+                    "stack used: %zu\n",
+                    hal_get_tick(), hal_get_heap(), hal_get_stack());
     }
   }
 }
@@ -103,7 +103,7 @@ int main(void) {
   mg_http_listen(&mgr, "https://0.0.0.0", http_ev_handler, NULL);
 
   MG_INFO(("Initialised. CPU clock: %lu MHz", SystemCoreClock / 1000000));
-  MG_INFO(("RAM used: %zu, free: %zu", hal_ram_used(), hal_ram_free()));
+  MG_INFO(("Heap used: %zu, stack used: %zu", hal_get_heap(), hal_get_stack()));
   MG_INFO(("Crash record: %M", mg_print_crash_record));
 
   for (;;) {

tutorials/stm32/nucleo-h723zg/minimal/mongoose_config.h

@@ -28,6 +28,8 @@
 
 // Crash report support. Health record lives in the .mg_health region, see link.ld
 #define MG_ENABLE_HEALTH 1
+#define MG_HEALTH_HEAP_USED hal_get_heap()
+#define MG_HEALTH_STACK_USED hal_get_stack()
 
 // mdash.net device management service support
 #define MG_ENABLE_MDASH 0